Justification:H. erectus is listed as Vulnerable (VU A4cd) based on inferred declines of at least 30% caused by targeted catch, incidental capture, and habitat degradation. While there is little information on changes in numbers of the species, there is indirect evidence to suggest that declines have taken place and are continuing. This listing is consistent with the precautionary approach of the IUCN.

Hippocampus erectus is traded for use as aquarium fishes, curios and traditional Chinese medicine (TCM) (Vincent and Perry, in prep.). This species is also incidentally caught, as bycatch, in shrimp trawl and other fisheries in Florida (Baum et al. in review), Mexico (J. Baum, unpublished data), Central America (Belize, Honduras, Nicaragua) (J. Baum, unpublished data) and South America (Argentina, Brazil) (I. Rosa and J. Baum, unpublished data). This species is also affected by habitat degradation due to coastal development and pollution. Given that H. erectus is among the most commonly traded seahorse species, particularly for ornamental display, fishers' and traders' evidence of declines in seahorse availability raise concern for this species.

Hippocampus erectus occurs from the southern tip of Nova Scotia in Canada, along the east coast of the USA, and south to Mexico, the Caribbean, and Venezuela. Small specimens from Brazil appear to be genetically distinct from the north Atlantic specimens and may prove to be a separate species (S. Casey, in litt. in Lourie et al. 1999). Further research is needed.

Project Seahorse trade surveys conducted between 2000–2001 indicated that seahorse numbers in the wild appear to have declined in the Western Atlantic (Caribbean and Gulf of Mexico), with fishers reporting decreases in catch of seahorses (proportion of declines that can be attributed to H. erectus is unknown). On the coast of Mexico 21/29 fishers in five locations reported declines in seahorses due to the shrimp trawl fishery. Of the 14 fishers who provided quantified catch estimates, eight estimated declines between 75–90% in the past 10–30 years (J. Baum unpublished data). In Brazil 25/29 fishers surveyed reported declines in seahorse catches due to heavy fishing pressures (I. Rosa, unpublished data). In Honduras 70% of interviewed fishers (n=9) believed there has been a decline in abundance (J. Baum, unpublished data). While we recognize that these surveys and reported population declines do not encompass the global range of H. erectus, we have chosen to take the precautionary approach of assigning VU.

Hippocampus erectus occur in water up to 73 m, and are associated with aquatic vegetation such as mangroves, seagrass, sponges, and floating Sargassum, as well as sponges (Lieske and Myers 1994, and McAllister 1990 in Lourie et al. 1999, Fish and Mowbray 1970). Hippocampus erectus can be found at the surface and bottom of both shallow water and deeper areas of channels in bays, along beaches, in or near salt marshes, and over oyster beds and weed-covered banks (Hardy 1978).

This species may be particularly susceptible to decline. The limited information on habitat suggests they inhabit shallow sea-grass beds (Lourie et al. 1999) that are susceptible to human degradation, as well as making them susceptible to being caught as bycatch. All seahorse species have vital parental care, and many species studied to date have high site fidelity (Perante et al. 2002, Vincent et al., in review), highly structured social behaviour (Vincent and Sadler 1995), and relatively sparse distributions (Lourie et al. 1999). The importance of life history parameters in determining response to exploitation has been demonstrated for a number of species (Jennings et al. 1998).

Hippocampus erectus is traded dried as traditional medicine (TM), curios and live for aquariums (Vincent and Perry, in prep.). This is a popular aquarium fish in North America. In Florida alone, thousands of H. erectus are collected each year for the aquarium trade (P. LaFrance, unpublished data). Hippocampus erectus is Brazil’s 6th most important marine ornamental export (Monteiro-Neto et al. 2000). In addition to being sold as TM, H. erectus are sold as curios in Mexico along the Caribbean coast (J. Baum, unpublished data). Hippocampus erectus are often brought up as bycatch by shrimp trawling operations in Florida (Baum et al. 2003), and in Mexico seahorse population declines are attributed to indirect harvesting by the shrimp trawl fishery (J. Baum, unpublished data). In Central America H. erectus are brought up in the shrimp trawls in Belize, Honduras, and Nicaragua, and are exported as TCM, or sold on both coasts as curios (J. Baum, unpublished data). Similarly in South America H. erectus are among the bycatch of shrimp trawls in Mar del Plata, Argentina (L. Magnasco in litt. to A. Vincent 23 May 1999), and in Brazil (I. Rosa and J. Baum, unpublished data).

The preferred habitat of H. erectus is also declining due to coastal development, pollution, and increased sedimentation. For example, in NE Brazil the development of shrimp farms has destroyed much of the coastal mangrove habitats where seahorses live (J. Gomezjuardo in litt. to A. Vincent Sept. 1999).

The entire genus Hippocampus was listed in Appendix II of CITES in November 2002. Implementation of this listing will begin May 2004. Full monitoring of the trade is underway in the United States, however this is dependent on traders’ declarations. Seahorses are listed under Title 68 (Rules of the Fish and Wildlife Conservation Commission) of the Florida Administrative Codes. The targeted fishery for the aquarium trade in Florida is monitored and regulations are in place, such as a limitation on the number of commercial harvesters, however the non-selective exploitation is not monitored in any state. Hippocampus erectus are considered threatened in the states of Sao Paulo and Rio de Janeiro in Brazil. Their status has not been evaluated in the other states